1. Field of the Invention
The present invention relates generally to the art of communications, and more specifically to managing data communications between multiple independent subsystems.
2. Description of the Related Art
Many of today's deployed commercial, corporate and government systems, such as nuclear power monitoring and control system, telephone systems, medical system, or other operational systems of any form found in a variety of scenarios are constructed as a collection of two or more independent components, modules or subsystems realized in hardware and software. Constructing a suite of independent components or modules affords product designers and manufacturers the ability to create and deploy subsystems that perform specific functions that are a subset of the complete device or system.
Designs that take advantage of allocating functions to a plurality of specialized subsystems must include a communications mechanism to enable the subsystems to interact. Subsystems may share or communicate control and status information between each other to realize complete system functionality. These communications are typically implemented using a communications protocol that specifies a uniform or consensus format that the subsystems use to transmit and receive information to each other.
Many types of computing and communication systems and devices transmit control and status signals between subsystems over a fixed wire or cable using a standard cable interface, such as Universal Serial Bus, Ethernet, etc. Recent developments have made it highly desirable for subsystems to communicate over a wireless network, thus reducing or eliminating the need to use fixed wire cables or backplanes to connect subsystems.
Current wireless implementations based on the Bluetooth™ communications protocol can become unsuitable for interconnection of subsystems forming safety critical system products that typically are interconnected using a fixed wire cable.
A major problem that may result in a hazardous situation when implementing the above-mentioned wireless Bluetooth communications protocol in a safety critical environment may occur within the operation of the slave device subsystem. Such a slave device subsystem, in a medical application, may include a remote control mechanism or a foot pedal that may mistakenly connect to and unintentionally interact with a foreign or separate master computing platform subsystem. For example, a wireless foot pedal in operating theater A may pair and connect to computing platform A while a surgeon uses the foot pedal during the procedure to control computing platform A. During the conduct of this procedure, another surgeon activates wireless foot pedal in operating theater B and initiates the Bluetooth ‘pairing’ process. The wireless foot pedal in operating theater B pairs and connects to computing platform B and a surgeon uses the foot pedal during the procedure to control computing platform B.
However, a slave device, i.e. foot pedal, may pair with multiple master devices, i.e. computing platform controller systems, in a Bluetooth environment. In the foregoing example, the wireless foot pedal in operating theater B also pairs and connects with computing platform A. In this situation, the surgeon in operating theater B is controlling computing platform s A and B simultaneously while the surgeon in operating theater A is also controlling computing platform A. The simultaneous operation of an computing platform from two wireless foot pedals can create confusion, disrupt a delicate operating procedure, and can potentially cause injury or even death to the patient in operating theater A. The surgeon in operating theater B may successfully control computing platform B in an effort to perform a procedure while unaware that he is simultaneously sending the same control input or signals to computing platform A. The surgeon in operating theater A may observe this interference, but remains unable to address the situation other than to discontinue the procedure, being forced to shut down computing platform A.
Overall system integrity is paramount to designing and deploying safety critical systems. Thus, today's designers are faced with a difficult and complex implementation challenge to ensure wireless communications between desired subsystems provide the required level of safety in, for example, an operating theater environment.
Furthermore, the communications protocol employed in the construction of safety critical systems must provide the ability for a slave device to exclusively pair and connect with a pre-selected master device ensuring the slave device is only communicating with a single master device at any given time.
Based on the foregoing, it would be advantageous to provide a wireless connection for use in safety critical systems that overcome the foregoing drawbacks present in previously known Bluetooth communications protocol designs used in the design of safety critical systems.